Wire enameling die



March 13, 1962 P. J. ZERWES WIRE ENAMELING DIE 2 Sheets-Sheet 1 Filed Sept. 4. 1959 March 13, 1962 P. J. ZERWES 3,024,762

WIRE ENAMELING DIE Filed Sept. 4, 1959 2 Sheets-Sheet 2 jfl/tver/c 7 07 1 1a ffewwea United States Patent Ofifice 3,024,762 Patented Mar. 13, 1962 3,024,762 WIRE ENAMELING DIE Paul J. Zcrwes, Chicago, Ill., assignor to Chicago Magnet Wire Corp., Chicago, 111., a corporation of Illinois Filed Sept. 4, 1959, Ser. No. 838,328 2 Claims. (Cl. 1l8125) This invention relates generally to filament coating apparatus and more particularly, relates to improvements in an enameling die structure for use in such apparatus.

This application is a continuation-in-part of my copending application, Serial No. 736,215 filed May 19, 1958 for the invention entitled Wire Enameling Die, now Patent No. 2,986,116.

The die structure of said co-pending application is especially advantageous for use in continuous coating processes where a filament is unreeled for passage through a liquid coating bath and then, through the die to obtain a uniform coating thereon. For instance, such a process is used in coating or enameling of electrical magnet wire with a liquid insulating material which is very viscous. Thereafter the coated wire is baked to set and dry the coating material. The structure of said application generally is comprised of a pair of telescopically assembled die parts movable relative one another for opening and closing the die. Thus, the die parts are required to be rotated one relative the other and moved rectilinearly along the axis thereof to open and close the die, said movements being the same for opening as Well as closing the die, albeit reversed in order of succession.

To permit manipulation of the die parts, same were provided with knurled ends axially displaced one relative the other. Further, the structure of said co-pending application contemplated angular movement between the die parts of a relatively substantial part of a revolution to obtain the desired registry and mis-registry of the entrant means for the filament. This structure limited somewhat the ease and facility with which the die could be handled under actual operating conditions where coated with liquid coating material of a highly viscous character such as used in coating electrical magnet wire.

In addition, the die structure of said co-pending application contemplated mounting of the die either on a wall of the liquid coating bath or on structure separated from the bath without any freedom of lateral movement during passage of the filament axially through the die. Such dies ordinarily are mounted in groups on a multiple die-holder assembly so that a plurality of filaments can be coated simultaneously. It is highly desirable that the die be permitted free lateral movement relative the direc tion of movement of the filament therethrough so that any strain on the filament during passage through the die is substantially avoided and hence, breaking of the filament is rendered more infrequent or substantially eliminated.

Accordingly, it is a principal object of the invention to provide an improved construction for enarncling die of the character described which embodies a construction capable of achieving the desirable advantages enumerated above.

An important object of the invention is to provide a die structure of the character described which is substantially smaller than the die structure of said application; which permits a relatively shorter angular movement between the die parts thereof for achieving the positions of registry and mis-registry of the entrant means of the die; and which includes novel means enabling operation of the die conveniently and rapidly as a result of said shorter angular movement.

Another object of the invention is to provide a die structure of the character described having novel means enabling the die to be mounted for floating movement on a multiple die-holder transverse to the direction of passage of the filament through the die. An ancillary object of the invention is to provide, in combination, a die structure having said novel mounting means and a mounting pin enabling such lateral floating mounting of the die on a multiple die-holder assembly.

The foregoing and other objects of the invention will become apparent from the ensuing description in which a preferred embodiment has been disclosed in detail and illustrated in the accompanying drawings. Minor variations in structure and arrangement of the several parts of the invention are contemplated without departing from the scope or sacrificing any of the advantages of the invention.

In the drawings:

FIG. I is a fragmentary side elevational view of a plurality of die structures embodying the invention mounted for floating movement transverse to the axes of the dies.

FIG. 2 is a fragmentary side elevational view of said die structure shown engaged by a mounting pin.

FIG. 3 is an elevational view of said die looking toward the end thereof having the coating forming aperture.

FIG. 4 is a top plan view of a plurality of said dies mounted for operation on a multiple die-holder assembly.

FIG. 5 is an elevational view taken from the rear end of the die opposite that of FIG. 3.

PEG. 6 is a top plan view of the die with the parts axially displaced one relative the other.

FIGS. 7 and 8 are transverse sectional views taken through said die structure and each engaged with a set wrench for moving the die parts shown partially, the die being illustrated closed in FIG. 7 and open in FIG. 8.

Referring now to the drawings, the die structure embodying the herein invention is designated generally by the reference character 10. The general principles of operation of the die 10 will be seen to be substantially the same as for the die of said co-pending application. Die 10 is formed of a pair of parts 12 and 14 of suitable configuration and dimension to permit one to be telescopically fitted within the other and hence, the part 12 will be considered the outer one and the part 14 the inner one of the pair. Each of the parts are of substantially uniform, circular cross-section and preferably formed of metal which is compatible with the coating liquid to be used for the filament enameling process.

The outer die part or shell 12 is open at its end 16. Said end 16 has an enlarged annular formation 18 thereat provided with a pair of transverse grooves 20 on opposite sides thereof. At its opposite end, the shell 12 has an axially extending terminal formation 22 which is tapered along the exterior flattened surface 24 to the extremity 25 of the formation. The formation 22 is generally semi-cylindrical to provide a semi-circular opening 26 whose center of curvature is coincident with the longitudinal axis of the shell. The terminal formation 22 has a flat inner face or surface 28 (FIG. 6) which also is coincident with the axis of the shell. The extremity of the formation 22 may be seen to be linear. A semi-cylindrical groove 30 is formed in surface 28 with its axis coincident with the axis of shell 12. A continuous, longitudinally extending slot 32 is provided in the outer wall of the shell opposite the formation 22 which extends from opening 26 to the end 16 of the die part. The slot 32 is in the nature of a guide for inserting and removing a filament in a radial movement and constitutes part of the entrant means of the die 10.

The inner die part 14 has an open rear end and an axially extending tapered formation 34 at its opposite end of semi-cylindrical configuration, The formation 34 also has a flat inner face or surface 36 coincident with the longitudinal axis of the shell 14. A semi-cylindrical groove 35 is formed in said face 36 which extends from the linear extremity 38 to communicate with the interior of the shell. The groove 35 is identical in configuration to the groove 30 so that when the die parts are telescoped and the formations 24 and 34 matingly engaged with their inner faces 28 and 36 juxtaposed, a circular opening is formed comprising the coating forming aperture of the die. The size of the respective grooves in the terminal formations 24 and 34 is selective, depending upon the desired diameter for the coated filament. A longitudinally extending slot 42 is provided in the exterior wall of the shell 14 opposite said formation 34 which extends from end to end of the shell, and cooperates with slot 32 to form the entrant means of the die. The end 44 of shell 14 is open and the length of the shell 14 is substantially equal to the length of the die part 12 so that when the die is closed (as seen in FIG. 2), the shell 14 is accommodated entirely on the interior of the shell 12 with the ends 16 and 44 having their end faces substantially flush. Extending axially outward from said end 44 of the die part 14 is a lug or car 46 which is perforated.

As seen in FIG. 6, the rear end 44 of the inner shell does not have an enlarged formation as does the corresponding inner die part in said co-pending application. Further, the means provided on the die 10 for operably mounting same is distinctive. In actual practice, a plurality of the dies are mounted on a multiple die-holder assembly designated generally 50 in FIG. 4. Said holder 50 includes a housing 52 on the interior of which are secured a plurality of die-holding pins 54 which protrude through a side of the housing. The pins 54 are arranged parallel and laterally spaced apart uniformly in a common plane and the dies are mountable between adjacent pairs of the pins 54. The housing may be installed on the liquid bath or on a structure separate from the bath. This may be done in any one of a plurality of ways easily comprehended by the skilled artisan.

Each of the pins is of elongate, generally rectangular cross-section and preferably tapered at its outer extremity 56. The opposite surfaces 58 of the pin which are longer in dimension are smooth with the edges rounded to facilitate relative sliding movement between the pin and the die engaged therewith. The means on the die for cooperating with said pins 54 to mount the die comprise a pair of slots 59 in diametrically opposite surfaces of the circumferential wall of the shell 12 and a pair of similar slots 60 in diametrically opposite surfaces of the circumferential wall of the shell 14. The slots 59 and 60 are located so that when the die is in closed position, each slot 59 is aligned with a slot 60 on opposite sides of the die. Each aligned pair of slots forms a guide channel into which a pin 54 can be engaged, the die being supported by a pair of said pins one on opposite sides of the die. Accordingly, the aligned slots 59 and 60 are of complementary shape to suitably seat the pins 54.

Referring to FIGS. 1 and 4, the die 10 is shown installed on the holder between the pair of adjacent pins 54A and 543. In addition, the pin 54A cooperates with the pin 54C to support the die 10A and the pin 54B cooperates with the pin 54D to support the die 10B. Further, as seen in FIG. 1, the depth of the aligned slots in which each pin is engaged is predetermined to permit some clearance between the bottom thereof and the adjacent lateral face 60 of the pin so that the die is permitted limited lateral movement in opposite directions transverse to the axis of the die. This relieves any undue strain on the filament 62 in its passage through the die.

The die 10 is further distinguished from the die of said co-pending application in the novel structure provided enabling the die 10 to be operated more easily and conveniently. The inner die part 14 has a protruding perforated car 46, as previously explained. The lug 46 and the grooves 20 provided in the outer die part 12 are cooperatively arranged to permit their being engaged by die part engaging means provided on the set wrench shown partiaily in FIGS. 7 and 8 and designated generally 65. The full structural details of said wrench 65 are contained in my co-pending application, Serial No. 838,321 filed September 4, 1959, now Patent No. 3,008,448, for the invention entitled Set Wrench for Wire Enameling Die. As explained therein, the set wrench includes a first die part engaging means 66 and a second die part engaging means 67. The engaging means 66 has a hook formation 68 adapted to be engaged in the grooves 20 of the die part 12 for rotating said die part 12 relative the die part 14. The engaging means 67 includes a pin 69 adapted to be engaged with the perforated lug 46 for moving the inner part 14 relative the die part 12 in a direction along the axis of the die 10. Reference to said application Serial No. 838,321 will provide full details of the manner in which wrench 65 is operative.

As seen in FIG. 7, the die 10 is in closed position with the aperture having the filament 62 engaged therethrough. The passageways 32 and 42 comprising the entrant means are arranged in a mis-registry position. In FIG. 8, the die is in open position which will have been achieved by first moving the die parts 12 and 14 axially one relative the other and then rotated one relative the other to align the slots 32 and 42. It should be noted that the slots 32 and 42 are located one with respect to the other so that only a small fractional part of a complete revolution is required to rotate the die parts from their position in FIG. 7 to that of FIG. 8 and vice versa to again close the die with filament 62 automatically engaged in the coating forming aperture.

It will be seen that the invention provides a wire enameling die comprised of a pair of die parts telescopically engaged one with the other, said die parts being movable one relative the other for opening and closing the die, said movement including an angular component of movement and an axial component of movement, the angular component being a small fraction of a revolution for opening and closing the die. The invention contemplates a die of the character described having novel means for mounting same for free, limited movement transverse to the axis of the die and means enabling the die parts thereof to be moved one relative the other for opening and closing the die by means of a tool without human hands touching the die parts, It is believed that the invention has been described in suflicient detail to enable a complete understanding thereof and the advantages achieved thereby.

In the claims where the invention has been defined, it is intended that the language thereof be construed broadly commensurate with the progress in the arts and sciences achieved thereby.

I claim:

1. A wire enameling die comprising, a pair of substantially cylindrical die parts having terminal formations adapted to be matingly engaged to form a coating aperture at one end of the die when the die is closed, said die parts being open at their opposite ends, each die part having a longitudinally extending slot in the circumferential wall thereof, said die parts being telescopically engaged and movable in succession along an arcuate path and a rectilinear path for engaging the terminal formations and arranging the slots mis-aligned one relative the other in the closed position of the die, and in reverse order of movement to align the slots one relative the other and separate the terminal formations in the open position of the die to permit insertion of the wire, the inner one of the die parts being contained substantially entirely within the outer one of the die parts in said closed position of the die, said slots being located to permit relative arcuate movement of the shell members only along a small fractional part of a full revolution of the die parts to align and mis-align said slots, said inner die part having a perforated lug protruding outward of said open end thereof.

2. A die as described in claim 1 in which said die parts have slot formations on opposite sides intermediate the ends thereof for operatively mounting the die for limited free movement transverse to the axis thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,811,505 Kennedy June 23, 1931 2,238,687 Flynn Apr. 15, 1941 2,351,110 Davidson et al. June 13, 1944 2,986,116 Zerwes May 30, 1961 

